1. Field of the Invention
The present invention relates to a backlight assembly and a display device having the same.
2. Description of the Related Art
Display devices are devices that visually display data. Examples of display devices include liquid crystal displays (LCDs), electrophoretic displays, organic light-emitting displays, inorganic electroluminescent (EL) displays, field emission displays, surface-conduction electron-emitter displays, plasma displays, and cathode ray displays.
Of the above display devices, an LCD includes a liquid crystal layer between two transparent substrates and displays a desired image by controlling the light transmittance of each pixel according to the driving of the liquid crystal layer.
Because liquid crystals of such an LCD cannot emit light by themselves, the LCD includes a backlight assembly that provides light to the liquid crystal layer. The backlight assembly typically includes a light source unit, a reflective plate, a diffusion plate, a light guide plate (LGP), and various optical sheets.
Backlight assemblies are classified into direct-type backlight assemblies and edge-type backlight assemblies according to the position of the light source unit. In a direct-type backlight assembly, the light source unit is placed to face a lower surface of the diffusion plate. In an edge-type backlight assembly, the light source unit is placed to face a side surface of the LGP.
Generally, a light source unit used in an edge-type backlight assembly includes a light source which emits blue light and a wavelength conversion material which is located on the light source and converts blue light into white light. Accordingly, the light source unit provides white light to the LGP.
However, if the wavelength conversion material is located adjacent to the light source, its properties can be degraded by, e.g., the degradation of the light source. Therefore, the wavelength conversion material may be separated from the light source by more than a certain distance. To this end, a wavelength conversion member including the wavelength conversion material may be placed on an upper surface of the LGP.
In this case, the light source unit may provide the LGP with blue light, not white light. Most of the blue light provided to the LGP may be converted into white light by the wavelength conversion material disposed on the upper surface of the LGP. However, the blue light may also leak through side surfaces of the LGP, excluding a side surface facing the light source unit.
To prevent this leakage of blue light, the area of the wavelength conversion member may be increased to be greater than that of the upper surface of the LGP. However, there still exists a possibility of leakage of blue light due to the horizontal movement of the wavelength conversion member. In addition, if the area of the wavelength conversion member is increased to be greater than that of the upper surface of the LGP, it is difficult to realize a display device having a narrow bezel.